High concentration of coagulase-negative staphylococci carriage among bioaerosols of henhouses in Central China

• Published in: BMC microbiology Vol. 20; no. 1; p. 21
• Main Authors: Lu, Yuanqing, Lu, Qin, Cheng, Yiluo, Wen, Guoyuan, Luo, Qingping, Shao, Huabin, Zhang, Tengfei
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 28-01-2020; BioMed Central; BMC
• Subjects: Airborne microorganisms; Animal breeding; Animals; Antibiotic resistance; Antibiotics; Bacteria; Bioaerosol; Bioaerosols; Chickens - microbiology; China; Coagulase; Coagulase-negative staphylococci; Cytokines; Disease transmission; Distribution; Drug resistance; Drug Resistance, Bacterial; E coli; Environmental aspects; Farmers; Genes; Housing, Animal; Humans; Immunology; Inflammation; Inflammatory cytokine; Interleukin 10; Interleukin 6; Interleukin 8; Interleukins; Interleukins - metabolism; Livestock; mecA; MecA protein; Methicillin; Microbial drug resistance; Nasal Mucosa - microbiology; Opportunist infection; Oxacillin; Oxacillin - pharmacology; Pathogenic microorganisms; Pathogens; Penicillin; Physiological aspects; Poultry; Poultry housing; Poultry industry; Public health; Public health movements; Safety and security measures; Salmonella; Species; Staphylococcus; Staphylococcus - isolation & purification; Staphylococcus infections; Tetracyclines; China; Switzerland; Bioaerosol; Inflammatory cytokine; mecA; Antibiotic resistance; Coagulase-negative staphylococci
• ISSN: 1471-2180; 1471-2180
• DOI: 10.1186/s12866-020-1709-y

Coagulase-negative staphylococci (CoNS) are a group of opportunistic pathogens, which are widely spread in the environment. Animal breeding is an important source of pathogen spreading. However, the concentration and characteristics of CoNS in the bioaerosols of henhouses are unclear.
In this study, we showed that CoNS were significantly increased in bioaerosols of henhouses during the first 60 days, and reached 2.0 × 10
 CFU/m
, which account for 75.4% of total bacteria. One hundred and two CoNS isolates from bioaerosols and nasal swabs of farmers were further identified, covering seven species. Among these, 41.2% isolates were Staphylococcus sciuri, which was the predominant species, followed by S. equorum, S. saprophyticus, S. haemolyticus, S. xylosus, S. arlettae and S. gallinarum. There were high rates of resistance to oxacillin in CoNS (49.0%), which were defined as Methicillin-Resistant CoNS (MRCoNS), and 36.3% isolates contained resistance gene mecA. Bioaerosol infection models showed that, chickens exposed to aerosolized S. sciuri had significant induction of inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8 and IL-10 at 5 days post-infection (dpi) in lungs and at 7 dpi in spleens.
We reported a high concentration of CoNS in henhouses, and S. sciuri was the preponderant CoNS species. Antibiotic resistance analysis and bioaerosols infection of CoNS further highlighted its hazards on resistance and immunological challenge. These results suggested that, CoNS in bioaerosols could be one serious factor in the henhouses for not only poultry industry but also public health.